Meteorologists are using phrases like “extremely active” and “above-normal” and “historical” to describe the latest forecasts for the Atlantic storm season.
What they’re really saying is: this hurricane season could be very bad.
Two of the leading hurricane forecasters — Colorado State University and the National Oceanic and Atmospheric Administration’s Climate Prediction Center — released updated forecasts this week that predict a hyperactive and potentially dangerous storm season for the rest of this pandemic-stricken year.
“We do expect this to be one of the stronger seasons in the historical record,” said Gerry Bell, the center’s lead hurricane forecaster, on Thursday.
Warmer Atlantic waters and weaker wind currents are helping create the conditions for what could be an “extremely active” season, he said, that could create “stronger, and longer-lived storms than average.”
Meteorologists could run out of storm names if those predictions prove accurate. There are only 15 names left in what has already been an active season. Once those run out, storms will be named using the Greek alphabet.
That hasn’t happened since the catastrophic 2005 hurricane season, when six hurricanes made landfall — including Hurricane Katrina, which overwhelmed New Orleans’ levees and flood walls and drowned the city.
The bad news started on Wednesday, when Colorado State University issued an August forecast that now predicts 10 hurricanes could form in the next four months.
The new forecast raises its May prediction of named storms from 16 to 24 and calls for 12 hurricanes as we enter the season’s busiest months, late August through early October — though storms could form after the season officially ends Nov. 30.
Colorado State research scientist Philip Klotzbach said not to focus on the rise in named storms. Instead, worry about the number of hurricanes.
“What is big is forecasting 10 additional hurricanes after Aug. 5,” he said. “This is the most named storms and hurricanes we’ve ever forecast in an outlook.”
Those 10 are predicted to come after the two Category 1 storms that formed in July: Hanna and Isaias. It also predicts there will be five major hurricanes of Category 3 strength or greater with sustained winds exceeding 111 mph — powerful enough to damage buildings, destroy trees and cause massive power and water loss.
Then on Thursday the Climate Prediction Center issued its own grim August forecast. In May, those scientists predicted a 60 percent chance of an above-normal season.
Now they forecast an 85 percent chance of an above-normal season. The chance of a near-normal hurricane season has dropped to 10 percent — and a below-normal season is just 5 percent.
This is also the first time the center has predicted 25 named storms. The full forecast calls for the formation of 19 to 25 named storms; 7 to 11 hurricanes; and six major hurricanes.
Remember these forecasts include the nine storms — two hurricanes and seven tropical storms — that have already formed as of July 30. That’s a record and an early indicator of how active the Atlantic season has already been. The ninth storm of the year doesn’t typically form until Oct. 4.
The Climate Prediction Center based its latest forecast on these factors continuing for the next few months: warmer-than-average temperatures in the Caribbean Sea and tropical Atlantic; less vertical wind shear; and a stronger west African monsoon. These conditions are being driven by the Atlantic Multi-Decadal Oscillation, a decades-long phenomenon that reappeared in 1995 and has been influencing stronger hurricane seasons ever since.
Klotzbach pointed to a specific phenomenon for Colorado State’s forecast: Atlantic waters off the coast of western Africa now running about ¾ degree warmer than normal in celsius. It’s a common phenomenon that accelerated in July.
“It doesn’t seem like that much of a difference,” Klotzbach said. “But it is for the tropics.”
That is the result of a synergy between wind and water, Klotzbach said. If there were stronger winds blowing across that Atlantic region, it would help cool the waters and prevent that slight rise in temperature. Stronger shear would also help prevent storms.
But the winds are weaker, so the water isn’t being cooled and there’s less chance of tamping down future storms from forming.
“That is what they call a positive feedback loop,” he said, “where one condition feeds the other to create hurricane favorable conditions.”
Another factor is that the Saharan Air Layer is receding, so there will be less Saharan dust plumes blowing off the African coast and hampering the formation of Atlantic storms. La Niña could also develop in the eastern Pacific Ocean in the coming months, which would further weaken Atlantic wind shear.
The storm season that scientists are comparing these forecasts to is 2005, the most active season on record. That year a record 15 hurricanes and 28 named storms form — although scientists didn’t discover the 28th until after it was over.
The difference between 2005 and 2020 is that Atlantic waters were warmer and wind conditions were even more favorable for storm formation 15 years ago, Bell said.
“2005 was just unbelievable in how favorable the conditions were,” Bell said. “We’re not expecting them to be that favorable (this year). And by this time in 2005 we already had two major hurricanes.”
That was also the only year on record that storm names ran out. The season ended with the formations of Hurricanes Beta and Epsilon and Tropical Storms Alpha, Gamma, Delta and Zeta.
There is no correlation between seasonal predictions and actual hurricane strikes, however. A destructive storm could make landfall in any year, which is why Floridians should prepare every year.
The COVID-19 pandemic makes storm season even riskier. Emergency planners ask Floridians to hunker down at home if possible, and to only evacuate if absolutely necessary to save shelter space for those who need it.
Masks will likely be required at Florida storm shelters. Those who check into shelters may be required to bring two cloth masks per person (one to wear and one to wash), sanitizer and anything else they need to stay safe from the virus. Shelters will practice social distancing, and those who test positive for the virus or are symptomatic will be separated and may be sheltered in motel rooms.
The state also asks all Floridians to stock seven days worth of food, medicine and water, which is how long officials expect it will take to re-supply after a direct strike.
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2020 Tampa Bay Times Hurricane Guide
HURRICANE SEASON IS HERE: Get ready and stay informed at tampabay.com/hurricane
PREPARE FOR COVID-19 AND THE STORM: The CDC's tips for this pandemic-hurricane season
PREPARE YOUR STUFF: Get your documents and your data ready for a storm
PROTECT YOUR PETS: Your pets can’t get ready for a storm. That’s your job
NEED TO KNOW: Click here to find your evacuation zone and shelter